Weapons such as U.S. M249 Squad Automatic Weapon (SAW), a light machine gun, the M240B, a medium machine gun, as well as, foreign light machine guns, such as the Israeli Negev, and Singaporean Ultimax 100 are all designed to be hand carried into combat, as well as, being fixed position weapons. As carried weapons, these guns weight from 15 to 35 pounds and from 41 to 49 inches in length are unwieldy, to say the least. Therefore, any reduction in weight and length clearly adds to their portability and functionality, especially in combat situations.
A buttstock (or shoulder stock or simply stock) is a part of a rifle or other firearm (personal weapon) that may be held against a shooter's shoulder when firing the weapon. The buttstock provides a means for the shooter to firmly support the weapon and more easily aim it. The buttstock also transmits recoil into the shooter's body when so positioned and the weapon is fired.
Buttstocks on standard rifles, portable machine guns, and other shoulder-fired weapons customarily have stocks with a butt portion located a particular distance from the trigger. That distance is termed “pull length” or “length of pull.” The length of pull of most rifles is based on the arm length of a typical user. Problems may arise when the user's size varies from the typical user. With a smaller than typical user, the distance to the trigger is too great when the rifle is braced properly on the shoulder. Variation from correct fit results in increased likelihood of unsafe and inaccurate operation of the weapon.
A light weight, adjustable buttstock for a weapon allows a user to more easily transport and position the weapon; plus having incremental adjustments in the overall length of the weapon help to suit the user's particular “pull length”. Further, considering the overall length of light and medium machine guns, a length adjustment is generally necessary when—for example—the weapon is mounted in tight quarters; to provide proper clearance (especially when the user is wearing body armor), thereby allowing the user to comfortably get into position behind the weapon allowing for proper eye relief and to properly site the weapon as needed; to quickly enter and exit a vehicle when transporting the weapon; and for further ease in narrow hallways and doorways. The adjustable buttstock may contain a buffer recoil mechanism to attenuate excessive recoil of the weapon.
A variety of adjustable buttstocks have been developed and are known in the art. Some include adjustable cheek rests (see, e.g., United States Patent Application Publication No. US 2008/0028662—Abraham) while others (see, e.g., U.S. Pat. No. 7,162,822—Heayn) do not (both 2008/0028662 and U.S. Pat. No. 7,162,822 are hereby incorporated herein by reference); however, such prior art solutions do not provide the desired combination of weight, and the secure plus easy means of length adjustment necessary in combat.